Prices in Bulgaria for some items are around half that of Western Europe, and good bargains are to be had on shoes and leather goods as well as other clothing. Note that clothes from famous international brands, perfumes, electronic equipment, etc. often are more expensive than in other parts of Europe.
In Sofia and a few major cities you can find branches of international hypermarket chains like Carrefour, Kaufland, pennymarket, Hit, Billa, Metro, and other. There are also many local supermaket chains like Fantastiko, Familia, and Picadilly currently Part of Delhaze group. All Bulgarian supermarkets sell products of European quality. LIDL are now present in many locations around Bulgaria.
The Bulgarian unit of currency is the Lev лев, abbreviated "лв", plural: Leva, comprised of one hundred Stotinki. The Lev is pegged to the Euro at 1.95583 Lev for one Euro which is the same rate as for the former Deutsche Mark, to which the Lev had previously been pegged 1:1. 1 Lev is roughly US$ 0.63 and GBP 0.40 as of 07/2012.
Shopkeepers and other businesses in Bulgaria will usually not accept foreign money, although many will accept the euro. Bulgaria remains a largely cash economy in the rural areas; but in major cities, credit cards are generally accepted.
In most cities there are many money exchange offices which are marked with signs that say "CHANGE". Most are legitimate, but some may rip you off. For example, they advertise a very competitive rate on the outside, but on the inside, there is a tiny sign with the "official" rates, and these are much worse – so always make sure to ask how many leva you will get for your money before you actually hand it over, and calculate yourselves e.g., using your mobile phone how much money you would expect to get. If you now refuse the transaction because the rate suddenly changed, they will make all kinds of unjustified assertions e.g., "I already entered it into the computer, it cannot be stopped", but you if threaten to call the police immediately while raising your voice so that other tourists look your way, they usually will let go immediately.
It is much safer to exchange your money at a bank. Banks apply little or no commissions, and generally offer good rates, although they are slightly worse than at a non-criminal change bureau. Higher commissions may be applied to traveller's cheques. Old, dirty or very worn bank notes may be refused. Never exchange money out on the street. Beware of people on the street who offer high rates of exchange or who may ask you to make some change for them.
Over the past years the ATM network in Bulgaria has grown considerably, making it relatively easy to obtain cash from the numerous ATMs in Sofia, as well as in all other major cities and resorts. The national credit/debit card circuit BORICA (http://www.borica.bg), to which all ATMs in the country are hooked up, accepts VISA/Plus, Visa Electron, MasterCard/Cirrus, Maestro, American Express, Diners Club, and a number of other cards.